The present invention relates to a godet of the type disclosed in U.S. Pat. No. 3,581,060. PA1 In known heated godets, which are normally constructed according to the design described in U.S. Pat. No. 3,581,060, the temperature sensors in the form of thin bars, are inserted into the godet casing parallel to the axis of rotation. This entailed, in particular in the case of godets with several heating zones, that it was necessary provide in the godet jacket, starting from its front end and distributed over its circumference, a number of bores of different depth corresponding to the number of heating zones, which resulted, in particular in the case of godets rotating at high speeds, not only in a considerable weakening of the godet casing, but also in unbalances which were complicated to remove. PA1 Known from DE-A 1 955 938 is a draw roll for advancing a yarn with a rotatable casing having one heated zone. Arranged in the interior of the casing is a stationary heating element. A flat temperature sensor is located on the heating element. The heating element and the temperature sensor are separated by an insulating cover. PA1 In the embodiment of DE-A 1 955 938, the temperature of the casing is measured indirectly, since there is an air gap between the temperature sensor and the casing. PA1 This measuring technique has also the disadvantage that a temperature fluctuation is registered, which does not occur necessarily also on the casing, since the temperature gradient in the air gap is dependent on the width of the air gap. PA1 Conditioned both by manufacturing tolerances and by natural wear, the air gap may vary. To maintain a constant air gap, it is necessary to minimize manufacturing tolerances and a possible wear. This again results in that the manufacturing costs of a godet increase accordingly. PA1 Having in mind the foregoing disadvantages, it is the object of the invention to achieve a satisfactory temperature measurement of the godet casing. PA1 To accomplish this object, it is proposed to arrange the temperature sensor on the inside surface of the godet casing, in particular parallel to the godet shaft. The temperature sensor is a measuring arrangement enclosed by an insulating cover with exposed tapping contacts leading outward via conduction paths.
The temperature sensor is arranged on the heating element facing the inside surface of the casing. The spacing between the temperature sensor and the inside surface of the casing is from about 0.3 to 1 mm. The air gap should correspond to about the boundary-layer thickness of the air, since it allows to maintain the most direct heat transfer.